Oral versus Intravenous Fludarabine as Part of a Reduced-Intensity Conditioning for Allogeneic Stem Cell Transplantation

Background: In 2003, oral fludarabine was introduced in the USA for the treatment of patients with hematologic malignancies as an alternative to its intravenous (i.v.) formulation; in 2008, it was introduced in México while the i.v. formulation was withdrawn. Accordingly, i.v. fludarabine had to be replaced by oral fludarabine as part of the conditioning regimen employed to conduct allogeneic stem cell transplantation in México. Methods: Nonrandomized retrospective analysis of 55 patients conditioned with oral fludarabine compared with 113 patients conditioned with the i.v. formulation. In addition to fludarabine, the conditioning regimen included oral busulfan and i.v. cyclophosphamide. Donors were HLA-matched siblings. Results: The clinical features of the two groups were comparable. There were no statistical differences in time to neutrophil engraftment, time to platelet engraftment, acute graft versus host disease rate and nonrelapse mortality at day 100. The overall survival of patients allografted with oral fludarabine was better than those allografted with i.v. fludarabine: 62 and 33% at 67 months, respectively (p = 0.0006). Discussion: Oral fludarabine can replace its i.v. formulation as part of reduced-intensity conditioning regimens with no deleterious effect on any of the early transplantation outcomes.